ATI MACH64 - wrong colors

[Marco Wilka <wilka@gno.de>]

Hi,

I am using Debian unstable on a PowerMac 4400 with an ATI MACH64 VT
graphics adapter and have the following problem when
using XFree86:

 - the colors are only correct when in 8-Bit-Mode
 - 16 bit depth/16 bit fbbpp yields in "psychedelic" color shifts
 - when using 24 bit depth, red shows up as blue, and everything
   that is meant to be blue appears as brown
 - (15 bpp doesn't work at all)

This problem occurs with kernel image 2.2.20 and 2.4.18 as well as
with xserver version 4.1 and 4.2. Kernel command line arguments
don't seem to affect my xserver's behaviour in any way. If I start
with BootX instead of quik and use the "No video driver" option,
the screen output is rendered unreadable.

Was anyone successful to get the xserver working in more than
8 bit on a stock 4400? Anything I could find on the web on that
topic didn't lead to anything so far, so any help would be
appreciated.

Thanks in advance,

Marco